Objectives: This study compared incidence rates, stage at presentation, and cause-specific mortality of nodular and superficial spreading melanoma along the rural-urban continuum in Kentucky. We compared resulting patterns in our data with sample demographic and other potential factors, including population by county and primary care provider rate.
Methods: Retrospective patient data were extracted from the Surveillance, Epidemiology, and End Results database from 2010 through 2017. These data were supplemented by environmental, demographic, and socioeconomic data derived from publicly accessible databases. Correlation and χ2 analyses were used to test for significant differences in outcome variables by US Department of Agriculture Rural-Urban Continuum Code (RUCC) categories and other potential predictor variables.
Results: Incidence rates by Kentucky county were not associated with RUCC or population; likewise, there was no relationship between stage at presentation and RUCC category. There was, however, a highly significant association between cause-specific mortality and RUCC; patients from rural areas were significantly more likely to die from melanoma than those in urban areas. This overall difference was due to differences in mortality for superficial spreading melanoma.
Conclusions: Our results suggest that a disparity in patients' ability or tendency to access primary care and/or specialist providers postdiagnosis may be critical factors in determining the ultimate outcome of a melanoma diagnosis. Further studies should explore the availability of dermatologists and/or treatment options for melanoma in rural areas. Our data also provide additional support for inclusion of melanoma subtype in the American Joint Committee on Cancer guidelines.